This invention relates generally to toy vehicle and particularly to boosters or accelerators which are utilized therein.
A large number of toy vehicle tracksets or playsets which are produced by practitioners in the art comprise closed loops of track portions which allow continuous operation of one or more toy vehicles traversing the closed loop trackway. The toy vehicles used in such closed loop trackways may either be free-wheeling unpowered vehicles or vehicles which utilize an onboard power drive mechanism. In the use of unpowered vehicles on closed loop trackways, practitioners often provide devices for accelerating the toy vehicles upon the trackway. Such accelerating devices are known generally in the art as xe2x80x9cboostersxe2x80x9d and typically include one or more motordriven rotating wheels adjacent a portion of the trackway. As a vehicle passes through the portion of the trackway occupied by the booster, the rotating wheel temporarily engages the passing toy vehicle and imparts energy thereto. The most common type of booster utilized employs a pair of spaced apart wheels on either side of the toy vehicle travel path which operate in conjunction to engage the passing toy vehicle from both sides and impart energy and acceleration thereto.
Not surprisingly, a substantial importance is placed upon the structure of the rotating wheels used in such boosters. The most common type of booster wheels employ disc-shaped members formed of a resilient foam material or the like. The objective is to provide frictional engagement with the passing toy vehicle to an extent sufficient to allow the rotating wheel to accelerate the toy vehicle. A further objective of such booster wheels is the resilient deformation of the booster wheels to accommodate a variety of differently sized and shaped toy vehicles. For example, U.S. Pat. No. 3,636,651 issued to Lohr et al. sets forth a TOY VEHICLE PROPULSION UNIT operative upon a closed circuit trackway such that the toy vehicle traverses the trackway and passes through the propulsion unit during each circuit. The propulsion unit includes a motor drive coupled to a rotatable booster wheel supported above the travel path of the toy vehicle. The booster wheel includes a generally hemispherical flexible member which is rotated at high speed and which deforms to engage the upper surface of the toy vehicle as it passes through the booster or propulsion unit.
U.S. Pat. No. 5,052,972 issued to Suimon et al. sets forth a DRIVE DEVICE FOR TOY AUTOMOBILE having a booster section supported above a toy vehicle trackway. The booster section includes a rotating flexible wheel having a generally cylindrical shape which engages the upper surface of the toy vehicle passing through the booster unit.
U.S. Pat. No. 3,590,524 issued to Beny et al. sets forth a TOY VEHICLE ACCELERATOR having a pair of booster sections supported in a common housing. Each booster section includes a pair of generally cylindrical rotating resilient booster wheels which engage the sides of toy vehicles passing through either portion of the toy vehicle booster.
U.S. Pat. No. 3,559,335 issued to See sets forth a TOY VEHICLE ACCELERATION MECHANISM having a rotating booster wheel supported above or, in an alternate embodiment, along side the travel path of a toy vehicle. The rotating booster wheel engages the vehicle and accelerates it through the trackway.
U.S. Pat. No. 3,641,784 issued to Sims et al. sets forth an ACCELERATOR FOR A VEHICLE TOY utilized with unpowered freely rolling vehicles upon a trackway. The accelerator includes a motor drive and a pair of spaced apart gear coupled booster wheels which engage the toy vehicle passing through the booster station and accelerate the vehicle.
U.S. Pat. No. 4,070,024 issued to Hamano sets forth a CONTINUOUS RACETRACK HAVING VEHICLE ACCELERATING DEVICE utilized in a continuous racing game having a trackway provided with separate paths along which vehicles race. The accelerating device includes a plurality of resilient spokes associated with each of the paths. The spokes are mounted for rotation and are radially oriented such that the ends of the spokes extend into the paths and impart acceleration to the toy vehicles.
U.S. Pat. No. 4,174,587 issued to Morin et al. sets forth an AIR TURBIN OPERATED VEHICLE ACCELERATING TOY having a base with a roadway portion formed therein. The base defines opposed slots on each side of the roadway within which engaging rollers are rotatably mounted. An air pump is provided which operates tubin means coupled to the drive rollers.
U.S. Pat. No. 5,067,413 issued to Kiuchi et al. sets forth an APPARATUS FOR CONVEYING TRAVELABLE BODY in which traveling power is transmitted one of a plurality of travelable bodies which are positioned on at least one end of the alignment.
Additional examples of conventional booster apparatus for toy vehicles which impart acceleration thereto using one or more rotating resilient wheels are set forth in U.S. Pat. No. 5,165,347 issued to Wagner, U.S. Pat. No. 5,299,969 issued to Zaruba, U.S. Pat. No. 5,899,789 issued to Rehkemper et al., U.S. Pat. No. 6,241,573 issued to Ostendorff et al., and U.S. Pat. No. 3,633,902 issued to Worden. In a related art, U.S. Pat. No. 5,402,730 issued to Salter et al. sets forth a PLATEN DRIVE UNIT utilized in propelling platens of vehicles moving along a track. The drive unit may be readily used at any portion of the track because it acts as a castor about a kingpin assembly. This substantially reduces the effects of roller scrub on curved track portions.
Accordingly, it is a general object of the present invention to provide an improved booster for a toy vehicle trackset. It is a more particular object of the present invention to provide an improved booster wheel structure for use in toy vehicle boosters.
In accordance with the present invention, there is provided a resilient flexible booster wheel formed of a flexible thin-walled toroid segment which provides improved flexibility, frictional grip, and accelerating characteristics not found in the prior art booster wheels.
The present invention is implemented by a booster wheel for use in a toy vehicle booster, said booster wheel comprising: a flexible thin-walled member forming a concave generally cylindrical wheel having a side wall portion, a top wall portion and a curved portion therebetween; plate means secured to the top wall portion for coupling to a rotation source; and a plurality of flexibility altering apertures formed in the flexible thin-walled member, the flexibility altering apertures being sized and positioned to provide a desired resilient and flexibility characteristic for said booster wheel.